ABU DHABI Ñ Saudi Arabia has pledged to protect its oil holdings in wake of an Al Qaida strike in the largest oil port city along the Red Sea.

Saudi officials said authorities would redouble efforts to guard oil and petrochemical facilities throughout the kingdom in wake of the killing of five Western engineers. They said the Al Qaida attack did not harm operations at the petrochemical plant in Yanbu, jointly owned by ExxonMobil and Saudi Basic Industries Corp. About 5,000 guards have been deployed around Saudi oil facilities.

[On Monday, about 90 employees of ABB-Lummus and their dependents prepared to leave Saudi Arabia, Middle East Newsline reported. The casualties of the Al Qaida attack on May 1 were Western engineers from the U.S.-based company, which said it would end its project at the petrochemical and refinery facility in Yanbu.]

"Saudi Aramco is keenly aware of its responsibility for ensuring the safety and wellbeing of employees, their families and company facilities," the kingdom-owned Saudi Aramco said. "The company's security is, in effect, on alert at all times. Facilities like refineries and terminals are guarded by multiple levels of armed Saudi Aramco security personnel working in close coordination with Saudi government forces."

Yanbu's port exports more than 400,000 barrels of oil per day. The city also contains the Samref oil export refinery.